It is very important to transform biomass-derived waste into useful materials with high performance. In this report, the N, O, P multiple heteroatom-doped activated porous carbon materials with enhanced electrochemical performance are prepared using durian shell-derived hydrochar. The as-prepared activated carbon materials show a characteristic of moderate specific surface area, micropore-dominant pore structure and multiple heteroatoms doping. As electrode in supercapacitor, the as-prepared N, O, P-doped porous carbon material can deliver a specific capacity of 184 F g-1 at a current density of 0.5 A g-1 in 1 M H 2 SO 4 aqueous solution and shows excellent cycle stability with a retention rate of *88% after 10000 cycles. In addition, in the redox electrolyte of H 2 SO 4 and KI aqueous solution, N, O, P co-doped activated porous carbon can provide a capacitance of * 560 F g-1 at 2 A g-1 (corresponding to energy density of 12.4 Wh kg-1 at a power density of 318 W kg-1). This work provides a novel way to enhance the electrochemical performance of the biomass waste-derived carbon, helping to further boosting their application in energy storage field.

We have fabricated Sb70Se30/HfO2 superlattice-like (SLL) structure thin films for phase change memory by magnetron sputtering method, and investigated the effect of the HfO2 layer on the crystalline characteristics and phase change behavior of Sb70Se30/HfO2 thin films. The experimental results show that as the HfO2 thickness increases, the crystallization temperature rises, the data retention capacity increases as well as the band gap widens, which is beneficial for improving the thermal stability and reliability of Sb70Se30/HfO2 thin films. It was also found that the HfO2 composite layer inhibited the grain growth of the Sb70Se30 thin film, reducing the grain size and resulting in a smoother surface. In addition, the volume fluctuation of the Sb70Se30/HfO2 thin films changes by only 5.58 % between amorphous and crystalline. The threshold and reset voltages of the cell based on Sb70Se30/HfO2 thin films are 1.52 V and 2.4 V respectively. We found that the HfO2 composite layer plays a significant role in improving thermal stability, refining grain size of Sb70Se30 phase change films and reducing device power consumption.

No abstract

No abstract